<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        iframe {
            width: 500px;
            height: 500px;
        }
    </style>
</head>
<body>
    
    <!-- <div class="box">
        1
        <p></p>
        <p></p>
    </div>
    <div class="box">
        2
        <p></p>
    </div>
    <div class="box">
        3
        <p></p>
    </div>
    <div class="box">
        4
        <p></p>
    </div> -->
    
    <!-- <iframe src="" frameborder="0"></iframe>
    <a href="#ii" >哈哈</a>
    <iframe src="" frameborder="0" name="ii"></iframe> -->

    <div class="g" id="g"></div>
    
    <script>
        
    //   var a = document.querySelector(".box");
    //   var b = a.querySelector("p");
    //   var c = a.querySelectorAll("p");

    // var d = window.innerHeight;
    // var e = window.innerWidth;
    // var f = window.length;

    var g = document.getElementById("g");
    var i = 0;
    var times = setInterval(function () {
        ++i;
        g.innerText = i;
        if (i == 5) {
            clearInterval (times);
        }
    }, 1000);

    
        
        
        

    </script>
</body>
</html>